Modern Animal: Hippopotamus>> The anthracotherium(Anthracotherium magnum), also known as an anthracothere, meaning ‘coal beast’ is a genus of extinct artiodactyls ungulate mammals that existed from the Oligocene period to the Mid Miocene period. This would calculate to be roughly 34 to 16 million years from present. The name ‘coal beast’ was given to the anthracothere as their first fossils were found in France in Paleogen-aged coal beds. When you compare the anthracotherium's appearance with the modern day hippopotamus, you will see that they are both very much alike. The anthracotherium however,is much skinnier and smaller than the hippo with a narrow head. It is often said that pigs resembled the species's appearance. Molecular research and fossil records have also found that the anthracotherium is proposed as the sister group of the Cetacea i.e dolphins and whales.
The following report will explore the habtat, extinction pressure, behavioural, structural and physiological adaptations of the anthracotherium.
Scientific Classification Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Artiodactyla Family: Anthracotheriidae Sub-Family: Anthracotheriinae Genus: Anthracotherium Labelled diagram of the anthracotherium
Habitat As mentioned before, the anthracotherium existed from the Oligocene epoch (Oligocene: 34 to 23 million years ago) to the Mid Miocene (Miocene: 23 to 5 million years ago). During this time, the weather was constantly changing. Thus, the anthracotherium was forced to adapt to the forever-changing climate and environment and were constantly migrating from one place to another.
Anthracotherium fossils were found in lignite and other swamp deposits leading to the belief that the species’ habitat was specialized to only swampy environments (see Figure #4). There structural adaptations also suggest that they lived in habitats similar to those of the modern hippo. However, researchers found that the species actually had a very diverse range of habitat choices as well as diet. On the other hand, investigations have also shown that the last of the species had adapted to an aquatic lifestyle.
Their migrating behaviour could have been the reason for this diversity. During the Oligocene period, the continents continued to drift to the positions they are in today. The first groups of anthracotheriums must have migrated sometime in the early Oligocene epoch as there was still a land bridge crossing between Europe and North America. This would have caused fossils of this extinct species to be found in a very large range including Europe, Asia, North America and Africa (see Figure #3). By looking at the map below, it can be seen that the anthracotheriums were distributed mostly on the southern hemisphere where the area was surrounded by warm temperatures and tropical (warm/wet) and arid (dry/warm) areas. The miocene epoch was similar to what is shown below, but warmer.
The anthracotherium lived during the Miocene and the Oligocene epoch, both part of the tertiary period. During the Oligocene and the Miocene epoch, the places the anthracotherium inhabited had a tropical or sub-tropical environment as mentioned before (see Figure #3) with warm and moist conditions. However, the anthracotheriums that lived during the Oligocene epoch lived in or very close by open woodlands and grasslands. These areas became abundant as the climate began to cool in this epoch thus providing areas close-by for the species to graze on.
Structural Adaptation #1 One particular structural adaptation that displays quite a difference from the modern hippo is the anthracotherium’s long, narrow and slender head shape/skull. This is very different from the modern hippo as they have a completely opposite skull structure that is very broad and big. The shape of an animal is usually evolved to fit the way of feeding. The anthracotherium’s head is wider in size near the neck area and gradually gets narrower as it reaches its snout. This could have helped the species by allowing its front, narrower part of its face, especially the mouth to reach food that perhaps may be caught between small gaps. The environmental pressure that could have given rise to this adaptation may have been ongoing climate changes. It could have been that the constant change in the environment made it more difficult for plants to grow, therefore making it harder to find food. The anthracotherium has adapted by eating a diverse variety of food, unlike the modern hippo that graze only on short grass. Most importantly, having a narrow head shape gives them the advantage of finding more food when food sources are scarce.
Structural Adaptation #2 Another structural adaptation of the anthracotherium is their feet. The anthracotherium had four or five toes on each one of its four feet. Their feet have adapted to their environment as it is rather broad and is well adapted for walking on soft mud. This helps the species as they have a semi-aquatic lifestyle, thus they will always be in contact with damp, soft ground. Fossil findings have shown that the anthracotherium lived in dense, swamp areas (see Figure #4). With well-adapted feet, the anthracotherium will be able to walk on soft mud without trouble of perhaps sinking in too deep. The environmental pressure that could have given rise to this adaptation could be that they were gradually evolving to become attuned to a semi-aquatic lifestyle. It could be that the species were slowly turning away from their terrestrial lifestyle to the water to perhaps avoid the increasing heat during the epoch.
Behavioural Adaptation #1 A behavioural adaptation of the anthracotherium is that they tend to migrate from one territory to another to suit the warm climate they need. Researchers after observing the hippo population found that migration was a behaviour also found in modern hippos. They found that modern hippos would only migrate under certain circumstances such as when males lose a territorial combat and only if it is necessary. The anthracotherium has adapted this behaviour to ensure that they get to live in the specialized semi-aquatic habitat that they require despite any major seasonal changes. This migration behaviour helps the species by leaving certain areas to avoid certain seasons e.g. rain season that they are possibly not well adapted to and instead move to new areas with a better environment. This ensures that the anthracotherium can stay in the type of environment they are adapted to and move away from those that they are not. The environmental pressure that could have led to the rise of this adaptation could very likely be the ongoing changes in the environment. During the time the anthracotheriums existed, the climates were constantly changing. Migration, however, allowed the animals to leave from one place to another and back again. Perhaps it was more beneficial to migrate as there might be more food provided or a better environment.
Behavioural Adaptation #2 Another behavioural adaptation of the anthracotherium is their nocturnal behaviour. Fossil records showed that the species lived a lot like the extant sitatunga, a swamp-dwelling antelope, that spent most of its life in swamps in reed beds and foraging (wandering around for food) in the evenings. Researchers believe that the anthracotherium had this similar lifestyle. Like the modern hippo, the anthracotherium is believed to spend their day resting by swamp areas with shallow water and retreating to grasslands to graze. This behaviour helps the anthracotherium as it enables them to stay in cool waters in the day away from the heat and the sun's rays. The anthracotherium had comparably more hair than the modern hippo having bristles of hair along the spine of the neck, however, it still isn't enough to protect their skin from the sun. This behaviour gives the species the opportunity to leave the water to graze in the dark to avoid the sun from harming their skin. The environmental pressure that may have given rise of this adaptation could very likely be the increasing temperature especially during the Miocene period. The increasingly warm temperature gave pressure to the species as their skin were not adapted for long-term sun exposure. Having this nocturnal behaviour allowed them to be protected from the sun by day and feed without risking sunburn. Physiological Adaptation #1
One particular physiological adaptation that the anthracotherium has adapted to their environment is their stomach. Their stomach consists of three chambers which are designed to absorb nutrition from foods with lower energy levels which they live off. This helps the species as it allows them to efficiently derive more nutrients despite the fact their food is not necessarily high in energy. Their stomach is made up of a parietal blind sac, the stomach/connecting tissue and the glandular stomach that connects to the intestines. The environmental pressure that may have given rise to this adaptation could be food scarcity. Anthracotheriums generally eat a diverse variety of food. However, it could have been that previously there weren't enough grass for them to graze on therefore forcing them to eat different sorts of food. Their solution to a better digestive system was a better adapted and complex stomach structure to be more fitted for their food intake. Extinction Pressure
The anthracotherium died out gradually from one continent after another. The species first disappeared at the beginning of the Ogligocene epoch from Europe and North America. At the end of the Miocene epoch, the species became extinct in Africa, then finally, Asia. The extinction pressure of the anthracotherium could very possibly be caused by major environmental shifts. The species had grown use to being forced to constantly adapt to the changing environment. However, it is very likely that it was a very significant change in the environment they were unable to adapt to that wiped them off the face of the earth. The last anthracotheriums in North America, Africa and Asia had a very specialized aquatic lifestyle. This made it difficult as it meant that they would not survive with the absence of water. Desertification would have been capable to shrink their habitat. Cooling trends also occured during the Ogligocene epoch causing tropical areas to change to a much cooler environment possibly too difficult for the hippos to adapt to. However, there might have been a much more major environmental shift, possibly as powerful as the Messinian salinity crisis also during the Miocene that could have completely taken away the species’ habitat as well as their source of food. This could have contributed to the species extinction as without water for their specialized aquatic lifestyle or their source of food, the species could not survive.
The anthracotherium (Anthracotherium magnum), also known as an anthracothere, meaning ‘coal beast’ is a genus of extinct artiodactyls ungulate mammals that existed from the Oligocene period to the Mid Miocene period. This would calculate to be roughly 34 to 16 million years from present. The name ‘coal beast’ was given to the anthracothere as their first fossils were found in France in Paleogen-aged coal beds. When you compare the anthracotherium's appearance with the modern day hippopotamus, you will see that they are both very much alike. The anthracotherium however,is much skinnier and smaller than the hippo with a narrow head. It is often said that pigs r
The following report will explore the habtat, extinction pressure, behavioural, structural and physiological adaptations of the anthracotherium.
Scientific Classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Family: Anthracotheriidae
Sub-Family: Anthracotheriinae
Genus: Anthracotherium
Labelled diagram of the anthracotherium
Habitat
As mentioned before, the anthracotherium existed from the Oligocene epoch (Oligocene: 34 to 23 million years ago) to the Mid Miocene (Miocene: 23 to 5 million years ago). During this time, the weather was constantly changing. Thus, the anthracotherium was forced to adapt to the forever-changing climate and environment and were constantly migrating from one place to another.
Anthracotherium fossils were found in lignite and other swamp deposits leading to the belief that the species’ habitat was specialized to only swampy environments (see Figure #4). There structural adaptations also suggest that they lived in habitats similar to those of the modern hippo. However, researchers found that the species actually had a very diverse range of habitat choices as well as diet. On the other hand, investigations have also shown that the last of the species had adapted to an aquatic lifestyle.
Their migrating behaviour could have been the reason for this diversity. During the Oligocene period, the continents continued to drift to the positions they are in today. The first groups of anthracotheriums must have migrated sometime in the early Oligocene epoch as there was still a land bridge crossing between Europe and North America. This would have caused fossils of this extinct species to be found in a very large range including Europe, Asia, North America and Africa (see Figure #3). By looking at the map below, it can be seen that the anthracotheriums were distributed mostly on the southern hemisphere where the area was surrounded by warm temperatures and tropical (warm/wet) and arid (dry/warm) areas. The miocene epoch was similar to what is shown below, but warmer.
The anthracotherium lived during the Miocene and the Oligocene epoch, both part of the tertiary period. During the Oligocene and the Miocene epoch, the places the anthracotherium inhabited had a tropical or sub-tropical environment as mentioned before (see Figure #3) with warm and moist conditions. However, the anthracotheriums that lived during the Oligocene epoch lived in or very close by open woodlands and grasslands. These areas became abundant as the climate began to cool in this epoch thus providing areas close-by for the species to graze on.
Structural Adaptation #1
Structural Adaptation #2
Another structural adaptation of the anthracotherium is their feet. The anthracotherium had four or five toes on each one of its four feet. Their feet have adapted to their environment as it is rather broad and is well adapted for walking on soft mud. This helps the species as they have a semi-aquatic lifestyle, thus they will always be in contact with damp, soft ground. Fossil findings have shown that the anthracotherium lived in dense, swamp areas (see Figure #4). With well-adapted feet, the anthracotherium will be able to walk on soft mud without trouble of perhaps sinking in too deep. The environmental pressure that could have given rise to this adaptation could be that they were gradually evolving to become attuned to a semi-aquatic lifestyle. It could be that the species were slowly turning away from their terrestrial lifestyle to the water to perhaps avoid the increasing heat during the epoch.
Behavioural Adaptation #1
A behavioural adaptation of the anthracotherium is that they tend to migrate from one territory to another to suit the warm climate they need. Researchers after observing the hippo population found that migration was a behaviour also found in modern hippos. They found that modern hippos would only migrate under certain circumstances such as when males lose a territorial combat and only if it is necessary. The anthracotherium has adapted this behaviour to ensure that they get to live in the specialized semi-aquatic habitat that they require despite any major seasonal changes. This migration behaviour helps the species by leaving certain areas to avoid certain seasons e.g. rain season that they are possibly not well adapted to and instead move to new areas with a better environment. This ensures that the anthracotherium can stay in the type of environment they are adapted to and move away from those that they are not. The environmental pressure that could have led to the rise of this adaptation could very likely be the ongoing changes in the environment. During the time the anthracotheriums existed, the climates were constantly changing. Migration, however, allowed the animals to leave from one place to another and back again. Perhaps it was more beneficial to migrate as there might be more food provided or a better environment.
Behavioural Adaptation #2
Another behavioural adaptation of the anthracotherium is their nocturnal behaviour. Fossil records showed that the species lived a lot like the extant sitatunga, a swamp-dwelling antelope, that spent most of its life in swamps in reed beds and foraging (wandering around for food) in the evenings. Researchers believe that the anthracotherium had this similar lifestyle. Like the modern hippo, the anthracotherium is believed to spend their day resting by swamp areas with shallow water and retreating to grasslands to graze. This behaviour helps the anthracotherium as it enables them to stay in cool waters in the day away from the heat and the sun's rays. The anthracotherium had comparably more hair than the modern hippo having bristles of hair along the spine of the neck, however, it still isn't enough to protect their skin from the sun. This behaviour gives the species the opportunity to leave the water to graze in the dark to avoid the sun from harming their skin. The environmental pressure that may have given rise of this adaptation could very likely be the increasing temperature especially during the Miocene period. The increasingly warm temperature gave pressure to the species as their skin were not adapted for long-term sun exposure. Having this nocturnal behaviour allowed them to be protected from the sun by day and feed without risking sunburn.
Physiological Adaptation #1
One particular physiological adaptation that the anthracotherium has adapted to their environment is their stomach. Their stomach consists of three chambers which are designed to absorb nutrition from foods with lower energy levels which they live off. This helps the species as it allows them to efficiently derive more nutrients despite the fact their food is not necessarily high in energy. Their stomach is made up of a parietal blind sac, the stomach/connecting tissue and the glandular stomach that connects to the intestines. The environmental pressure that may have given rise to this adaptation could be food scarcity. Anthracotheriums generally eat a diverse variety of food. However, it could have been that previously there weren't enough grass for them to graze on therefore forcing them to eat different sorts of food. Their solution to a better digestive system was a better adapted and complex stomach structure to be more fitted for their food intake.
Extinction Pressure
The anthracotherium died out gradually from one continent after another. The species first disappeared at the beginning of the Ogligocene epoch from Europe and North America. At the end of the Miocene epoch, the species became extinct in Africa, then finally, Asia. The extinction pressure of the anthracotherium could very possibly be caused by major environmental shifts. The species had grown use to being forced to constantly adapt to the changing environment. However, it is very likely that it was a very significant change in the environment they were unable to adapt to that wiped them off the face of the earth. The last anthracotheriums in North America, Africa and Asia had a very specialized aquatic lifestyle. This made it difficult as it meant that they would not survive with the absence of water. Desertification would have been capable to shrink their habitat. Cooling trends also occured during the Ogligocene epoch causing tropical areas to change to a much cooler environment possibly too difficult for the hippos to adapt to. However, there might have been a much more major environmental shift, possibly as powerful as the Messinian salinity crisis also during the Miocene that could have completely taken away the species’ habitat as well as their source of food. This could have contributed to the species extinction as without water for their specialized aquatic lifestyle or their source of food, the species could not survive.
Bibliography
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